<?php// content="text/plain; charset=utf-8"// Example on how to treat and format timestamp as human readable labelsrequire_once("jpgraph/jpgraph.php");
require_once("jpgraph/jpgraph_line.php");
// Number of "fake" data pointsDEFINE('NDATAPOINTS',500);
// Assume data points are sample every 10th secondDEFINE('SAMPLERATE',10);
// Callback formatting function for the X-scale to convert timestamps// to hour and minutes.functionTimeCallback($aVal){returnDate('H:i', $aVal);
}// Get start time$start = time();
// Set the start time to be on the closest minute just before the "start" timestamp$adjstart = floor($start / 60);
// Create a data set in range (20,100) and X-positions// We also apply a simple low pass filter on the data to make it less// random and a little smoother$data = array();
$xdata = array();
$data[0] = rand(20,100);
$xdata[0] = $adjstart;
for($i=1; $i < NDATAPOINTS; ++$i){$data[$i] = rand(20,100)*0.2 + $data[$i-1]*0.8;
$xdata[$i] = $adjstart + $i * SAMPLERATE;
}// Assume that the data points represents data that is sampled every 10s// when determing the end value on the scale. We also add some extra// length to end on an even label tick.$adjend = $adjstart + (NDATAPOINTS+10)*10;
$graph = newGraph(500,250);
$graph->SetMargin(40,20,30,50);
// Now specify the X-scale explicit but let the Y-scale be auto-scaled$graph->SetScale("intlin",0,0,$adjstart,$adjend);
$graph->title->Set("Example on TimeStamp Callback");
// Setup the callback and adjust the angle of the labels$graph->xaxis->SetLabelFormatCallback('TimeCallback');
$graph->xaxis->SetLabelAngle(90);
// Set the labels every 5min (i.e. 300seconds) and minor ticks every minute$graph->xaxis->scale->ticks->Set(300,60);
$line = newLinePlot($data,$xdata);
$line->SetColor('lightblue');
$graph->Add($line);
$graph->Stroke();
?>